Oxazinoquinolones useful for the treatment of viral infections

A compound of formula I

• or a pharmaceutically acceptable salt, racemate, solvate, tautomer, optical isomer or prodrug derivative thereof wherein:
• each X is independently O or S;
• Y is Cl, F, Br, CN or NO2;
• R1, R2, R3 and R4 are independently
• a) hydrogen,
• b) N3,
• c) CN,
• d) fluoro,
• e) trifluoromethyl,
• f) aryl,
• g) het,
• h) C1-8 alkyl, optionally substituted with R6 or OR7, or
• i) R1 and R2 or R3 and R4 together with the carbon to which they are attached form C3-8cycloalkyl or het;
• R5 is C1-8alkyl, which may be partially unsaturated and optionally substituted with one to three N3, halo, CN, R6 or R7;
• R6 is
• a) aryl,
• b) het,
• c) SOiR8,
• d) OR8,
• e) C(═O)OR8,
• f) C(═O)R8, or
• g) NR8R9;
• R7 is
• a) P(═O)(OR10)2,
• b) CO(CH2)jCON(CH3)(CH2)kSO3−M+,
• c) an amino acid,
• d) C(═O)C1-6alkyl, optionally substituted by NR10R10, or
• e) CO(CH2)nCO2H;
• R8 and R9 are independently
• a) hydrogen,
• b) C3-8cycloalkyl,
• c) aryl,
• d) het, or
• e) C1-8alkyl which is further optionally substituted with one or more aryl, het, halo, CN, CO2R10, SOiR10, OR10, NR10R10, CF3, or C3-8cycloalkyl;
• R10 is
• a) H or
• b) C1-8alkyl, optionally substituted with OH or OC1-4alkyl;
• R11 and R12 are independently
• a) hydrogen
• b) halo,
• c) NO2,
• d) CN,
• e) R6,
• f) SOiNR8R9, or
• g) C1-8alkyl, which may be partially unsaturated and optionally substituted with one to three N3, halo, CN, R6 or OR7;
• aryl is
• a phenyl radical, optionally fused with a saturated or unsaturated carbocyclic or heterocyclic ring;
• at each occurrence, aryl may be substituted with one or more halo, CN, CO2R10, SOiR10, OR10, NR10R10, CF3, C3-8cycloalkyl, or C1-4alkyl wherein C1-4alkyl is optionally substituted with OR10;
• het is
• a four- (4), five- (5), six- (6), or seven- (7) membered saturated or unsaturated heterocyclic ring having 1, 2, or 3 heteroatoms selected from the group consisting of O, S, and NW, wherein W is hydrogen, C1-4alkyl, C(═O)OC1-4alkyl or absent, wherein het is optionally fused with a benzene ring, a carbcyclic or a heterocyclic ring;
• at each occurrence, het may be substituted with one or more halo, CN, CO2R10, SOiR10, OR10, NR10R10, C1-4alkyl, CF3, C3-8cycloalkyl, or oxo;
• at each occurrence, a cycloalkyl may be substituted with C1-4alkyl, OR10, oxo, or a spiro fused het;
• i is 0, 1 or 2;
• j is 1, 2, 3, 4, 5, or 6;
• k is 1, 2, 3, 4, 5, or 6;
• n is 1, 2, 3, 4, 5, or 6;
• M is sodium, potassium, or lithium;
• and
• with the following provisos:
• a) at least one of R1, R2, R3 and R4 is other than hydrogen;
• b) where R1, R2, R3 and R4 are independently C1-8 alkyl, at least one of the alkyl groups is substituted with R6 or OR7.